Which is working combination for M20B25?

[nsbone_1988_520i]

I hv the following to play with:

A. 1 X M20B25 Manifold + i injector
B. 1 X M20B25 exhaust manifold
C. 1 X M20B25 camshaft
D. 1 X M20B25 engine block
E. 1 X M20B25 crankshaft
F. 6 X M20B25 Piston Connecting rod
G. 6 X M20B27 Piston
H. 1 X M20B25 Manifold + e injector (M20B27 engine)

No head B25 head, so what's the best combination?
A+D+E+F+G+M20B20 head? (since B27 head is flat?)