I am selling vintage API 325 Line amp cards for $150 each plus shipping of $6.00 and $3.20 insurance. This card can be modified to become a 312 mic pre. Also included with the card is a packet of information on the 325 card, the 312 card, and the 2520 opamp, including schematics and pinouts. I accept Paypal (preferred), cash, money orders or checks. (I am not doing volume discounts, but I only charge shipping on the 1st card.) reply to: email@example.com Paypal address: firstname.lastname@example.org Thank you.