Resin/Plastic Leviathan Dreadnought Parts Compatibility?

[Sothalor]

Currently the state of Leviathan Dreadnought kits entails:

• Plastic boxed kits from GW (chassis and weapons - two kits, melee and ranged loadouts)
• Plastic weapon frame kits from GW (melee and ranged)
• Resin individual weapon kits from Forgeworld
• Resin Legion-specific chassis kits from Forgeworld (currently Dark Angels, White Scars, Night Lords, & Blood Angels)

Does anybody have any direct experience or insight with compatibility between the plastic and resin kits? Specifically, I'm thinking of the Legion Leviathan resin bodies with the plastic weapon frame parts. Looking at sprue pics, it seems like they should work - the plastic weapon parts include the shoulder joint connections where the resin kit parts end, and I can't see how they wouldn't fit together just fine.

Has anybody built a Leviathan out of mixed kits? Any unforeseen surprises or things to be aware of?