4.3 in MGB

[RDChaplin]

Of those who converted to a 4.3 GM engine I am wondering if the firewall and transmission tunnel need to be modified?  Planning on a T5 tranny.  If the firewall was not modified, do you know what the front to rear balance is for this engine and trans combination?
Thanks,  Doug

[BMC]

Not to rain on your parade but why the 4.3L? There are better and lighter V8s and better fitting V6 engines that are not quite the weight and good power for the MGB.

Hope someone answers you soon otherwise.

-BMC.