318/360 spool mount bolts size

[Duster_71]

Hello all, Not sure if this is the correct spot for this but looking for some info. What size bolt do I need for the spool motor mounts going to the k-member perch? I'm working on a 74 Duster and switched the /6 k-member out with a v8 member. Additionally, is there anyone out selling correct 340/360 left side spool mounts that do not cost a small fortune? I have the 318-360 mount but would get the correct mount for a reasonable price,