No need for external oil return....
Open the returns up in the head.
Again if you want the motor to last, don't be cheap
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Best piece of advice so far!
Get threaded main restrictors. Since I now know the secret, ( thanks Drew) some plain 1/8 NPT internal plugs with about a 60 thou hole thru them will be good.
Also, you want to open the #5 main cap where the oil pump sits. Also, don't forget to shim the oil bypass about 3/16.
Also, you must notch the big end of the conrods and make sure you have correct rod clearance.
Get some good rockers that have some sort of adjustability to them. Restricted pushrods are not mandatory since you will be restricting the mains.
The pistons you have are not high compression.
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