quantum field theory - Pauli Villars Regularization

Consider the t-channel diagram of phi-4 one loop diagrams. Evaluated it is, with loop momenta p,

$\frac{\lambda^2}{2}\displaystyle\int\frac{d^4p}{(2\pi)^4}\frac{1}{(p+q)^2-m^2}\frac{1}{p^2-m^2}$

If I want to regularize this using Pauli-Villars regularization, which is the correct method? The procedure is to make the replacement $\frac{1}{p^2-m^2}\rightarrow \frac{1}{p^2-m^2}-\frac{1}{p^2-\Lambda^2}$.

My question is do I apply the reguarization to one term in the integral or both terms?

I've seen variations where the propagators become $\frac{1}{p^2-m^2}\frac{1}{(p+q)^2-m^2}\rightarrow \frac{1}{p^2-m^2}\frac{1}{(p+q)^2-m^2}-\frac{1}{p^2-\Lambda^2}\frac{1}{(p+q)^2-\Lambda^2}$ and also where we have $\frac{1}{p^2-m^2}\frac{1}{(p+q)^2-m^2}\rightarrow (\frac{1}{p^2-m^2}-\frac{1}{p^2-\Lambda^2})(\frac{1}{(p+q)^2-m^2}-\frac{1}{(p+q)^2-\Lambda^2})$

In the latter case one ends up with four terms and each term is then evaluated using a Feynman parameter and integrating over wick rotated momenta, obtaining a logarithmic expression.

I'm pretty sure I've also seen where it was only applied to one of the terms.

Which is correct? (or are they equivalent?)