We'll need some more information before we can help. I assume the Lucas stuff is the high zinc break-in product that company sells. Also...do you have solid lifters or hydraulic lifters (your machine shop will know). And the type of lifters and whether the shop did anything to adjust your valves will be of special interest also. I take it the engine was all assembled (including the head)? There isn't a section here, but you'll find lots and lots of discussion about this if you search the engine shop section of the forum.
As for setting timing, I've always set the number one piston to just before top dead center, removed the distributor cap and then look to see which hole in the distributor cap the tip of the rotor is pointing toward. Connect the number 1 plug wire to that hole, put your timing light between the plug and that particular wire, turn the ignition on and slowly rotate the distributor until the light flashes. Do this a couple of times, get that point where the light flashes and then tighten the distributor holding screw. You won't be perfect, but you'll be close. And then going clockwise from the number 1 hole in the distributor cap, connect the number 5, 3, 6, 2 and 4 spark plug wires in sequence.
You won't hurt the piston rings. The danger is damaging the camshaft/lifters. Today's oil doesn't have enough zinc in it, so break-in can be a bit challenging. Fortunately the 235's valve springs are not all that strong.
We'll wait to hear from you.
