If remember right the tappet adjustment is 16thou or .4mm for both inlet and exhaust.
Rip the rocker cover off...have to anyway. Turn the engine over till the timing mark on the pully lines up on the pin in the cover.
Try to move the rockers on no1...if they are loose and four are tight you are on TDC no1 other wise you are on TDC 4
If on TDC one,
From here you can adjust inlet exhaust on one, inlet two, exhaust three.
Turn the engine 360....one will be tight and 4 will be loose...so now you can adjust both inlet and exhaust on 4, inlet on three and exhaust on two.
If from the start....one tight and 4 is loose then start from four..ie reverse order.
Fastest way to set any inline engine.