You'd better be careful here. Depending upon what version of the Motorhome 413 you have (there were 413-1, 413-2 and 413-3 engines), you may have some problems. The version I personally had experience with had a gear driven camshaft that ran backwards off of a big gear on the crank. No timing chain in that version. If that is the case in YOUR engine, you'll have to get the parts to run a regular timing chaing. That includes the distributor gear, timing gears and chain.

Greg