1. Light is light, the meter which I have used for studio shooting on 4x5 film is the same meter which I also use for digital SLR. Digital SLR makers have set up their cameras to faithfully perform so that ISO 100 in digital is ISO 100 in classical film characteristics.
My Minolta Autometer VI incident light metering matches the result of metering an 18% gray card with my Minolta Spotmeter F matches the metering of the same gray card with my Canon dSLR.
2. If you mount your dSLR on your 4x5 camera, you will NOT record anything like your 4x5 film will (90x120mm of image), you will end up with 23.6 x 15.8 mm section of the 90x120mm 4x5 frame; if you can see enough to judge overall exposure you will have gotten lucky.
You might as well simply shoot a photo with the D60 (not rigged to mount on the 4x5 rear standard) and use those settings to shoot the equivalent photo with your 4x5. Better yet, go buy yourself an incident light meter which is not fooled by subject/scene brightness which is not 18% tonality.