Mike,
I would point you to
chapter 30 of the 1689 LBC for the details on Baptist requirements and observance of the Lord's Supper.
I know Baptist churches have different opinions on this. In this Baptist elders opinion, the main qualification to partake of the Lord's Supper is being a believer who is not living in unrepentant sin. I do not want to approach the Lord's Supper with a rigidity that the Lord did not intend. I suppose I would have two views towards those who participate. If you are a member of our church and you are not in unrepentant sin, you are to participate. If you are visiting with us and are Presbyterian, you would still be welcome to participate. If you intend to become a Baptist this issue will become moot. if you stay as an attender (but not a member) the elders will have to address this issue with you. It may result in your not being able to participate if you decide to attend for an extended period without applying for membership.