Howdy, my Pertronix HEI is not completely seated onto the block. There is about an 1/8th of an inch gap between the distributor body and the block. The motor is rebuilt, I forgot a gasket for the distributor and the bolt for the distributor clamp is longer than the original. So I'm thinking that the missing gasket is the cause of the of the gap? OR.... is the longer clamp bolt bottoming out?? Any help would be great.
Thanks

Sometimes you have to coax it a little. Don't force it with the hold down clamp. Try pulling it out and back in and turn the motor. The gasket is overrated. Most don't use one. I found the gasket compresses when you snug down the bolt and the timing changes from what you set it at.

make sure the oil pump drive rod is sitting right

the distributor rotates as it drops that last 1/8 inch and it has to drop onto that shaft right

2nd Sprint's response.
Pump rod has a double prong that engages a cross shaft pin on distributor gear.
Got'a try to figure where rod should be(get close enough) as distributor and cam gear mesh..
Sometimes I get it 1st try, other times takes several. May depend on how many beers I've had...