Autosol is good truckies have been using it for years. A cheap old school polish for alloy is a mixture of half brass and kero. The go to for the truckies atm is purple polish have not used it personally but gets great reviews
XF 5spd ain’t much chop, came with the 3.3, from memory same as a sigma. Better off with a 4 Spd. Hunt up a e-series 6 cylinder. This is a bell housing I modded a singlerail bel housing the bottom two are the new
It does support the top plenum cover couple of spot welds, directly below there is the pedal box. There is bolts on that area for the wiper motor assembly isn’t there? Support Just going of memory car to far away atm.