Lining the rabbet with Framers Tape won't do much good. It would slow down acid migration for some time, but it is not gas-impermeable, and acid would eventually get through it.
I suggest lining the rabbet with a metallized (foil) tape, which is gas-impermeable. Lineco makes the one I use; I buy it from Light Impressions (#2354), but all of the archival material suppliers should have a comparable product.
Also, to make a "pad" on the part of the frame's rabbet that contacts the face of the painting, apply a strip of "Volara". This is a 1/32" thick, black, adhesive-backed foam tape made for the purpose. I buy it in 1/2" wide rolls, from University Products (#018-1232).
As far as I know, that's the best you can do for an oil painting.
Unless...
The painting has heavy texture at its edges. In that case, you might want to use strips of 100% rag mat board as a rabbet pad.
Or, if that isn't enough, you can space the frame off the surface of the painting with offset clips for fitting. This method leaves a gap between the face of the painting and the frame -- usually less than 1/8" -- which can be unsightly; and dirt/debris/insects can accumulate in the gap, which might do more damage than the frame's contact would do.