I have experience with H&R wheel spacers. You can find the exact part number of the spacers you need at
www.hrsprings.com. I checked the ML MBZ series and they list about 5 different thicknesses.
I would suggest you opt for a 10mm minimum thickness spacer so you have a hubcentric lip to mount the wheel onto. Spacers thinner than 10mm do not have this lip extending from the front face of the spacer as there is no room to machine such a device. You will have to purchase longer lug bolts. I suggest using McGuard brand. They are highly chromed. If you have a wheel cover, then any cadmium plated bolt will work fine.
H&R's are a high quality spacer. I recently read a post regarding this other site,
www.wheeladapter.com but I cannot recommend them as I've no experience. From a machining standpoint though a precision spacer isn't hard to create. H&R anodizes the entire surface area.
As for the argument you are placing increased stress on the suspension due to the extended lever arm, this is true, but hardly detrimental. The same effect could be achieved with using a wheel with an incorrect offset of 15mm. The only difference here is the spacer is a separate piece between the wheel backface and the wheel bearing rotor assy.
Just remember to use a high quality anti sieze compound on the lug bolt threads and torque them properly, you'll not experience any difficulties. This assumes you won't have a rubbing issue as the suspension flexes. With the widened track it should handle noticeably better.
The McGuard website doesn't list their lug bolt selection. You need to find the part numbers from their catalogue.
razzmatazz
