is there a conversion kit to adapt a t-18 bell housing to a perkins 6 cylinder diesel? Or is there an adapter to put a np205 to a clark 5 speed? Or any advice.
I'm unfamiliar with the perkins specifically, but a lot of those industrial/equipment engines use a SAE bellhousing. There are about 9 different sizes depending on the manufacturer/application/etc. I don't know of any adapters offhand, but I have never looked for them. There are a few spicer transmissions that utilize the SAE #3 pattern. The SAE pattern is basically bolts evenly spaced around a circle, so having an adapter machined somewhere probably wouldn't be too difficult. A quick search turned this link up:
I've always wanted to put an off-highway diesel in a rig myself, so I'd love to see someone do it. Good luck & post up some pics if you ever start this project.