Something you wrote jogged a memory. There were categories for Ford, GM, Chrysler & Outlaw, which was.say, a Mustang with a Chrysler engine, etc. I can remember quite a lot of floppers with same engine as the body. There was a Camaro I saw at Lions with a Rat motor, & had 16 spark plugs. King Camaro??? Argh long time ago. Anyhoo, engine had plugs on both side of the heads. It sounded different compared to the other engines. They had to pull the heads to get to the inside plugs. I'm guessing the engine had dual mags. Saw the car run many times, don't remember seeing the engine. Back then, having a Chevy or Ford body with a Chrysler was heresy; now it's all they run. I have a friend also named Cliff, lives in Oregon. He was a crewman for Wild Willy Borsch, on both the AA/FA and the Charger F/C. Willy decided to run a Chevy rat motor in the Charger. At the time, it was cheaper to run than the Chrysler. but it never made the power the Chrysler made. Everyone told Willy he was nuts for switching. Some of the T/F cars were running Chevys then. Larry Dixon Sr ran in the 5's with a cast Rat. I think he was part of the Crager 5 second club. Dixon switched from a 426 Chrysler to the Rat, but he ran good with it. Guess that is why Willy switched.
Cliff, the 4 team categories you mentioned only occurred once, at the '69 Mfg. Meet.
During the first 2 years OCIR permitted mix 'n match FCs like the '67 Chapman Automotive Camaro and '68 Dick Loehr's Stampede Mustang, both hemi-powered. The '67-'68 were also invitation-only events. That is, Mike Jones/OCIR selected the 5 cars for each team. I preferred this method cause it guaranteed that the headliners would be in the show (more on this below). There were 6 teams at those early Mfg. Meets: Dodge, Plymouth, Chevy, Ford, Mercury and Pontiac. This is my favorite period because the majority of FCs had matching bodies and motors. Most even had the "proper" trans and rear ends! This was also the height of "psychedelic paint jobs," the era of cobwebbing, lace, wild striping and dramatic color fade patterns.
OCIR decided to change the MM format in '69. Due to the increase of Hemi-powered and AMC funny cars they created the "Wacky Racers" team. The name was borrowed from a Saturday Morning Cartoon show. Participating FCs included the Brutus Firebird, Frantic Ford (both Hemi-powered), ftrends and Doug's Headers Javelins, and even the Holy Toledo Jeep! The other 3 teams were Chrysler, GM and Ford-Mercury. Going from 6 teams to just 4 was compensated by increasing the team count to 8 cars per team.
The other major change to the MM was making it into a 2 day event w/ open qualifying on Friday. Yes, the race was now twice as long but each FC had to earn a spot on the teams. One could argue it created the best performing teams for the Saturday race but I just hated when the Eastern cars I waited to see didn't make the show! The most glaring example of this was Jungle Jim's '70 Camaro. After wowing SoCal fans w/ his tremendous fire burnouts in the previous month JJ was noticeably absent at the '70 Mfg. Meet.
Yes, the '71 King Camaro was the 16-plug, big block FC, campaigned by Dean LaPole.
However, I think the most impressive Chevy-powered FC after 1970 was the Burkhart-Therwhanger Camaro, the maroon and orange one.
Therwhanger won the very first IHRA race at Rockingham in April '71 over the Hawaiian-Butch Maas. Charlie also won a ton of match races that season and kept up w/ the Hemi's. I waited to see that FC all season but it failed to appear at the Mfg. Meet. Instead, Therwhanger tuned Kelly Chadwick's Chevy powered Camaro and he was one of the few to run in the 6.7 range while most were 6.8's at best!