How about the opposite: 300 engine on H rear

I know where there's a 300 (or was it a 350?, will have to look again) with a good engine but the rear end is ruined from sitting with water in it. Would the clutch from an H bolt onto a 300 or 350 flywheel or could you use the same clutch and simply ignore the IPTO drive part of it? Another way of asking, are the transmission input shaft splines different?

It's good to hear how you worked through this same swap. Sounds like it won't be too much hassle.

Donde estas? (Where are you?)

I'm in central Texas too.

I've been putting a 300U C169 engine in an I-4.

I used the entire I-4 back plate, flywheel clutch, and input shaft package with the 300 motor.

To mount the engine, I had to use the I-4 front accessory drive and cover, thats where the problems came in. 300U used 1/2 dowel pins (I-4, none) and larger 1/2 bolts (I-4, 3/8) in the face of the block. I had to step down the bolt holes in the block, drill the dowell holes in the acessory drive plate and shave the dowell pins flush with the plate. The 300U's magneto drive had a slightly different bolt pattern requiring me to use the I-4's.

Outside of needing the older I-4 front cover for its engine mount, it was all straight forward.

You will need the air cleaner and the pipe to the carburator from a super H, the h pipe is to small to fit the 300 carburator. There is no fitting in the back of the 300 head to connect with the air cleaner inlet pipe, it vents through the valve cover. A couple of fittings and a hose will fix this.

Use the fan off of the H, 300 fan is to large in diameter, 300 water pump works.

I may have forgotten something but don't think so. My e-mail is open if you need anything else. Dave