You might try a pressure tap in crankcase and use crankcase pressure. You will probably need a one way "check " valve in pressure line. Also a pump that works off vibes of engine works too. Then there is the cline regulator pump. If you handy...use just the pumping section of a Walbro carb. Now someone is going to say...just use a complete Walbro crab. The only thing they are big and ugly....besides....if you want to do ever thing the easy way...forget conversions, and buy a Ready to go engine!!!!!! I may do that some day. Capt,n