The LD-340 modded as per the MP books is an excellent t mod except the center divider wall should be left alone. Milling the divider is for a leagal cheats d works with high lift cams with a good bit of duration.
The TQ mod to the LD-340 is excellent by itself. For certain, space the carb up.
Now the RPM-AG is a better intake by a few scant ponies. The carb of choice should be a Holley and not a run of the mill cheapo Holley. Spend some dough on a nice serious unit and tune the heck out of it. It'll take the edge over the older units, but, not by much.