My 440 in my 63 is a 10.0 comp 906 headed quench eng. I had my blocked square decked and when I check it I use the same piston and rod in all 4 corners. That way you dont have to worry about difference in lenth from recontioned rods. I had my rods bushed for floating pins and they can be off a tad also so you have to use the same rod and piston in all 4 corner's. Now my chamber depth varied a good bit and that was alot of work getting them close. Mine were as much as .010 difference so I had to work them to get as close as I could. I got all my quench readings between .040 to .046 and I went with that. So with the 906 iron heads and 10.0 comp using the MP .557 cam and 37 total timing I have no ping at all and run fine on 92 pump. I know how it is on a tight budget. If you run it like it is let us know how you make out. Sure it will run and you may not have any ping but it could. If it does ping then back the timing up a few degrees and hope that works. Good luck , Ron