The porting seems to be working very well. I had to lean the mixtures slightly, but the bottom end response is better and the truck reaches peak RPM quicker.

I've got an OS Carb that I had planned on using on my S-25, but it doesn't fit the intake of the casing - the carb seems to big.

The carb has some sort of plastic sleeve around it, so perhaps if I can remove this sleeve, then maybe it will fit. Getting this sleeve off is going to be interesting though!