A direct bolt on requires a V8 Camaro/Firebird T5 or an Astro/Safari van T5. Those transmissions have the correct length input shaft and that is why they do not need an adapter plate. The V8 Camaro has a 26 spline IS and the Astro has a 14 spline. I have heard that you can take a 10 spline Jeep T5 IS and put it in an S10 (as long as the gears are the same) and that will allow you to keep a 10 spline clutch disc. I do not know if the Jeep IS is the correct length or not.
An S10/S15 truck T5 has an input shaft that is about 3/4" longer than the V8 Camaro and Astro examples above. Some people cut off the 3/4" and modify the input shaft splines or the clutch disc splines, or both. Other folks just buy an adapter plate that moves the T5 back about 1/2" to 5/8" and that corrects the situation.
I know nothing about a 228 bell housing, so I can't comment on that.
As far as bolt patterns go, the T5 has a Muncie pattern from 1982-92 for the Camaro and 1982-93 for the S10. I just learned today that some Astro T5 transmissions have a Ford pattern case. Mine has a Muncie pattern.
The 1993 and up Camaro T5 uses a FORD pattern case
The 1994 and up S10 T5 also uses a FORD pattern case.
Just this week I was looking at some photos and found something interesting. I talked to the owner of the bell housing in the photo below. He said the bell was from a Camaro with a T5. The bell clearly has the markings of a FORD case pattern T5 on it. The bell also has a small block Chevy pattern where it bolts to the block. So I am thinking you could use a 1993 and up Camaro T5 (FORD pattern case) with an older truck as long as you use this style bell. The bell has another set of holes that probably match a Muncie pattern.
Camaro bell with a FORD pattern - mates with a FORD case V8 Camaro T5 I am virtually certain that a V6 Camaro T5 can be made to work without an adapter plate as well. The splines in the V6 Camaro input shaft are cut much more along the length of the input shaft. Cutting off 3/4" would make the shaft the correct length. The input shaft should not need any other modifications.
Here are a few photos to compare.
S10 and V8 shafts. This photo shows that the S10 shaft is LONGER and that the splines are not cut long enough for the necessary clutch disc travel like they are on the V8 shaft.
Here's an Astro T5 IS. The notes are from the owner and I cannot verify accuracy but they look correct. This has the correct length IS and does not need an adapter plate.
This is a V6 Camaro input shaft. Other than being 3/4" longer than the Astro shaft, it is identical. The splines are cut along the length enough that cutting it shorter should be the only modification needed.
Lastly, the 82-92 Camaro T5 has a cable style speedometer drive but the shifter is at the wrong place to use in a bench seat truck. It can be used OK with bucket seats. The 1982-86 or possibly 1987 S10 and S15 has a cable style speedometer and these are getting very hard to find. If you find one, then the tail housing can be used on any other T5 and a small modification can be done to make the T5 have a cable style output. The 1987 and later S10 has an electric pulse speedo output which will work fine if you use modern style speedometer gauges that read a pulse.
1983 S10 Tail Housing with cable speedo output. 1985 S10 T5 This is a 1985 S10 T5 I bought last month. I was lucky to find it. It has a cable speedo output and you can see it also has a removable ratio adapter (Stuart Warner 0.733333) that slows down the speed of the cable for speed correction.
