You are well within normal weight tolerances... I see 70-80 grams pretty often. The new powered metal stuff is reall close on weight but the old forged rods are not.
-disagree , thats terrible spread on the balance
I `d be trying to get it done right some way --------and dam sure aint gonna switch rod caps around !
My 505 kit was race balanced by hughs engines , on a solid motor plate , no rubber bushings , u cant feel it running !