So I needed a chimera and the two griffons so to the closet of miniature holding I went. I opened the two Griffon boxes and found only one with all the parts to build a complete chimera. I happened to remember an old basilisk I picked up in a job lot of tanks years ago. The basilisk was built as a chaos basilisk when the previous owner acquired it. He had removed most of the chaos symbols and spikey bits but the worst part was that the gun mount had been broken. I had cleaned up the model and did a bunch of work to cover up where the chaos bits had been removed but the gun was another matter. I had drilled, pinned, puttied and carved but the gun just didn't look right, so it had gone back into the box.
I found the old Basilisk in storage and removed the base plate for the earth shaker cannon and shortly had the Griffon mortar base inside the hull. It wasn't perfect but it was good enough for government work. I assembled the second griffon and then a chimera from the parts in the first griffon box. After a good deal of greenstuff and fitting i had everything ready for primer.
The three after primer. A funny note is that I have had the two Griffon models still in the box for over ten years, I originally bought them in an auction at the now closed Games Workshop store in Concord NC. One good thing is the primer covered many sins on the old basilisk model.