t4 exclusive bike rack holes capacity??

[aris]

So, this is my problem. I recently upgraded my t4 exclusive to syncro.
I can no longer storage the spare tire underneath the van.
My thought is to use the holes of the back side where the bike rack is mounted, for a construction where it can hold the spare tire and mount a 2 bike rack over the spare tire with a usual spare tire bike rack!
The wholes are the original and they are made to hold weight.
Do you think there might be a problem for all this weight capacity?
Thanks in advance!