Forget my last post, that tach only works on 1 cyl. engines. I found this one and it seems to fill the bill for anyone wanting to put a tach on a late model tractor. It sells for 59.00 on Amazon. They say it will work on 1,2,4,6,8 cyl. engines. Check it out. Equus - Products - 8068 3-3/8" Tachometer (DIS) - Diagnostics Made Easy
B&S does produce a tach/hour meter for use on their engines. you should be able to pick one up at most any repair shop. they cost about $55 average. they are made for the 1 & 2 cylinder engines.