Thanks for reading my post. I'm new to this forum AND also new to sewing in general.  I've read a lot on the internet and I've probably learned enough to be dangerous.  SO, I thought I'd bring my questions to the experts.  I'm considering buying a Pfaff 145 H4 6/01 industrial walking foot machine.  It has had some modifications to it. Those include: it's been fitted with a larger diameter hand-wheel pulley (for lower torque).  It has a Large Hook/Bobbin from a Pfaff 545.  It's a single needle, c