File cabinet GPU server cluster

Has anyone attempted one of these with mATX boards? There are a number of excellent examples on the net (many based on IKEA’s Helmer el-cheapo cabinet) but they are all non-GPU versions and the ability to squeeze 1-2 GPU per board would appear non-existent. Would like to hear any success stories and parts lists if you have them. TIA

Best, V.

Bumping this myself.

Does anyone have recommendations for the smaller mini-itx boards with one or two x16 slots for use with the 400 series GPUs? TIA.