Second tyrant from 1 kit? Replacement parts?

So there is a lot of duplicated pieces in the tyrant kit. Enough to make me think I can make a truly horrific kitbash to make the spare parts into a second tyrant as I have put magnets on the main weapons.

The pieces I can not find suitable replacements for are as follows:

Legs, seen people use defilers for this and it seems like the only legs that are appropriate. Any other suggestions?

Shoulders, would assume the half circle spike things also from a defiler would work here.

Arms/side panels, green stuff cable horror would work I think stablized with a spure framework as base.

Nipple melts, found sponsor meltas from land raider and another HH kit that looks good.

Top weapons, 1 is left over from the already built one so just need to figure out if I want 2 rockets or cannons.