Find And Remove Letters?

I can use find and replace to remove the following, however as I would be doing the same process numerous times it would be very tedious.

I would like 2 VBA scripts.

1 - replace the following letters (uppercase & lower) in Column A and C replace A, V, N, Z, X, Q

so if it finds A it would remove A from the cell.

The cells may contain other letters including these one's i.e

A123XCB235 or
123VBN7779A

2 - The second independent code would replace the characters replace A, V, N, Z, X, Q with P, M, L, R, J, H ie. A becomes P, V becomes M etc...

Again the cells may contain other letters including these one's i.e

A123XCB235 or
123VBN7779A