Using QuickCheck to generate multiple arbitrary parameters for a given function

Context

I have the following function:

prop_SignAndVerify :: (PrivKey a b) => Blind a -> BS.ByteString -> Bool
prop_SignAndVerify bsk msg = case verify pk msg sig of
                             Left e -> error e
                             Right b -> b
  where
    sk  = getBlind bsk
    pk  = toPublic sk
    sig = case sign sk msg of
               Left e -> error e
               Right s -> s

I would like to do something like:

-- instance PrivKey RSA.PrivateKey RSA.PublicKey where...
genRSA :: Gen RSA.PrivateKey
genRSAMessage :: Gen BS.ByteString

main = do
  quickCheck . verbose 
  $ forAll genRSA 
  $ forAll genRSAMessage prop_SignAndVerify

That is, I would like to use explicit generators to generate arbitrary values for Blind a and BS.ByteString in the parameters of prop_SignAndVerify.

The code above, however, doesn't work, because the function forAll has type signature:

forAll :: (Show a, Testable prop) => Gen a -> (a -> prop) -> Property

This function runs the generator and apples the generated arbitrary value to (a -> prop), returning a Property. This Property however cannot be further partially applied; it hides the underlying function.

I think what we need for the above to work would be something like:

forAll' :: (Show a,  Testable prop) => Gen a -> (a -> prop) -> prop

Question

So my question is, how can I use genRSA and genRSAMessage over the parameters of prop_SignAndVerify, or is there an alternative approach?

Thanks