67' 318 crank in a 69' 340

Hey folks , I have a question and I would like to hear your thoughts on what I could do or should do .
A few years back I bought a 69' 340 short block and buddy threw in a complete low mileage 67' 318 ( never been apart ) . I tucked the two engines under the shop bench as I was busy working on the body of my 70' Dart Swinger . I dragged out the 340 short block today and realized that the pistons have the four valve relief cuts , pistons are recessed in the cylinder at TDC and the crank has the 1/8" parting line . Everything is pointing to a low compression rotating assembly in the 69' block . The flange on the crank is damaged and I knew it was damaged but thinking it was a 69' forged steel crank , I thought it could be repaired and remachined like new . Being a cast crank I think that is now out of the question .

I have searched the net looking to find out if the 67' 318 would have a forged crank or a cast crank . Some say forged and some say cast , nothing definative . The casting date is 8 / 10 / 67 , interestingly 50 years and 3 days old as of today .

This car is just going to be an old school fun driver , four speed , frame connectors , mini tubbed , springs relocated , Cragars , 325/50/15s , motor has refreshed 308 heads , LD340 intake , 340 manifolds and will have a small cam ( not sure what to use just yet ) all Taylored for cruising and with just a little additude to boot .

Is there any benefit to staying with the lower compression assembly in the 69' block ? Would you use the 67' 318 crank with the 340 rods and pistons ( still low compression ) have it all balanced or use 318 crank and 318 rods with 340 pistons ( higher compression ) and have it balanced ? This motor is going to be a low budget build and will rarely see much more than 4500-5000 rpm . I am a little ways away from tearing into the motor but I would like to know what I could do or what I should do . I'm looking forward to hearing your positive comments !

I appreciate your thoughts/comments and I thank you in advance !!!
Take care !!